Malabsorption and Small Intestinal disease Flashcards
what is the average length of the small intestine?
250-450cm
when does the small intestine reach its full length?
11 years old
how does the small intestine keep a low bacterial population?
presence of bile salts
digestive enzymes
presence of IgA
what are the symptoms of a small bowel pathology?
weight loss increased appetite diarrhoea (sometimes steatorrhoea) bloating fatigue
what is steatorrhoea?
fat malabsorption causes stool of high fat content stool less dense and floats pale and foul smelling may leave oily mark or oil droplets
what are the clinical signs of a small bowel pathology?
signs of weight loss signs of vitamin deficiency's clubbing aphthous ulceration scleroderma dermatitis herpetiformis
what small bowel condition are these signs most commonly found in;
- clubbing?
- aphthous ulceration
- scleroderma
- dermatitis herpetiformis
- crohn’s and celiac disease
- crohn’s and celiac disease
- systemic sclerosis
- celiac disease
what are the signs of Ca, Mg and vitamin D deficiency?
tetany
osteomalacia
what deficiency causes night blindness?
vitamin A
what are the signs of deficiency of thiamine and niacin? and from which vitamin group are these in?
vitamin B complex
thiamine = memory loss/dementia
niacin = dermatitis, unexplained heart failure
what is a sign of vitamin K deficiency?
raised INR/PTR
what tests are carried out for investigating small bowel structure?
small bowel endoscopy and biopsy small bowel barium meal follow through study CT scan MRI enterography capsule enterography white cell scan H2 breath test culture duodenal aspirate
what investigations are carried out to test for bacterial overgrowth?
H2 breath test
culture duodenal or jejunal aspirate
what is coeliac disease?
sensitivity to gliadin which is found in wheat, rye and barely
in coeliac disease there is an immune response via what enzyme?
transglutaminase
what is the pathology of coeliac disease?
inflammatory process via transglutaminase
partial or subtotal villus atrophy
increased intraepithelial lymphocytes
what tests can be carried out to investigate if its coeliac disease?
serology
- anti endomysial IgA
- anti-tissue transglutaminase IgA
- anti-gladin (in children)
distal duodenal biopsy HLA status (HLA DQ2/DQ8 in coeliac)
what is the treatment for coeliac disease?
withdrawal gluten from diet
will need referral to a registered dietician for guidance
why can a patients HLA status be inaccurate for diagnosing coeliac disease?
97% of patients with coeliac disease are HLA DQ2 or DQ8 however so is 30% of the population so could give a false positive
why might the seology test anti-tissue transglutaminase be inaccurate in diagnosing coeliac disease, and what can be done to make it more accurate?
selective IgA deficiency is not uncommon.
if someone has this then they may falsely show to have coeliac disease when they don’t.
therefore you have to test their IgA before and then the anti-tissue transglutaminase can only be sufficient in people who naturally make IgA
what is the clinical presentation of dermatitis herpetiformis and what condition is it commonly found in?
coeliac disease
- blistering
- itching
- scalp, knees, elbows, shoulders
- IgA deposits in the skin
what are some of the complications of celiac disease?
refractory small bowel disease small bowel lymphoma small bowel adenocarcinoma oesophageal carcinoma colon cancer
what are causes of malabsorption?
crohns disease coeliac disease infection- tropical sprue, HIV, Giardia lamblia Whipples disease Amyloidosis systemic sclerosis diabetes pseudo obstruction Iatrogenic - gastric surgery, short bowel syndrome, radiation chronic pancreatitis cystic fibrosis
what makes you more susceptible to Giardia lamblia? and what does this cause?
hypogammaglobulinaemia
malabsorption
small bowel overgrowth ca occur in any condition which affects what?
motility
gut structure
immunity
what test is used to diagnose small bowel overgrowth?
h2 breath test
what is responsible for the large surface area in the small intestine?
villi and large turnover of cells in crypts and villi
describe the pathology of coeliac disease.
inflammatory response via transglutaminase
causes partial / sub total villous atrophy
increased intraepithelial lymphocytes
what are some of the conditions that coeliac disease may be associated with?
dermatitis diabetes mellitus hashimotos autoimmune hepatitis primary biliary cirrhosis autoimmune gastritis sjogren syndrome IgA syndrome downs syndrome
